Advisable? I certainly wouldn't advise it - modafinil or melatonin, yeah, I've read a fair bit of material and think I know the minimal risks, but not testosterone. I'm a little concerned about the mixed bag I see in some of the case studies. For example, Andrew Sullivan has covered his experience with prescription testosterone:

• http://www.nytimes.com/2000/04/02/magazine/the-he-hormone.html?pagewanted=all
• http://andrewsullivan.thedailybeast.com/2011/09/the-subtlety-of-testosterone.html
• http://www.isteve.com/ManlyMolecule.htm